反应详情

A mixture of 12 g. of 4-[(2,4-diamino-5-pyrimidinyl)-methyl]-2,6-dimethoxycarbanilic acid ethyl ester and 2 g. of sodium hydride (50% dispersion in oil) in 100 ml. of absolute dimethylformamide was stirred at room temperature for 4 hours and then treated with 6.5 g. of ethyl iodide. After stirring at room temperature for 30 minutes, the dimethylformamide was removed at 60° C. under vacuum. The residue was taken up in 250 ml. of water and the precipitated product extracted with two 600 ml. portions of ethyl acetate. The ethyl acetate extract was washed with two 300 ml. portions of water, dried over magnesium sulfate and evaporated under vacuum. The residue was chromatographed on 350 g. of silica gel using ethyl acetate/alcohol (3:1) and there was obtained N-ethyl-4-[(2,4-diamino-5-pyrimidinyl)-methyl]-2,6-dimethoxy-carbanilic acid ethyl ester having a melting point of 165°-167° C. (recrystallization from ethyl acetate).

1. additionA mixture of 12 g
2. additiontreated with 6.5 g
3. customthe dimethylformamide was removed at 60° C. under vacuum
4. extractionof water and the precipitated product extracted with two 600 ml
5. extractionThe ethyl acetate extract
6. washwas washed with two 300 ml
7. dry with materialportions of water, dried over magnesium sulfate
8. customevaporated under vacuum
9. customThe residue was chromatographed on 350 g